Wife has betrayed me.........i am at my wits end?

While i was going through her handbag i found a letter from her mother, i have forbidden her to speak to this woman as she called me a fat lazy drunk. But now i see that behind my back she has been talking to this evil woman. I would move in with my lover but we are both on social security and we might lose some if we co habit, besides i need the money my wife earns in her 2 job to keep me going as my welfare does not go that far........what should i do about this turn of events?